@mikro-orm/core/events/EventManager.js

TypeScript ORM for Node.js based on Data Mapper, Unit of Work and Identity Map patterns. Supports MongoDB, MySQL, PostgreSQL and SQLite databases as well as usage with vanilla JavaScript.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.EventManager = void 0;
const utils_1 = require("../utils");
const enums_1 = require("../enums");
class EventManager {
    listeners = {};
    entities = new Map();
    cache = new Map();
    subscribers = [];
    constructor(subscribers) {
        subscribers.forEach(subscriber => this.registerSubscriber(subscriber));
    }
    registerSubscriber(subscriber) {
        this.subscribers.push(subscriber);
        this.entities.set(subscriber, this.getSubscribedEntities(subscriber));
        this.cache.clear();
        utils_1.Utils.keys(enums_1.EventType)
            .filter(event => event in subscriber)
            .forEach(event => {
            this.listeners[event] ??= [];
            this.listeners[event].push(subscriber);
        });
    }
    dispatchEvent(event, args, meta) {
        const listeners = [];
        const entity = args.entity;
        // execute lifecycle hooks first
        meta ??= entity?.__meta;
        const hooks = (meta?.hooks[event] || []);
        listeners.push(...hooks.map(hook => {
            const prototypeHook = meta?.prototype[hook];
            const handler = typeof hook === 'function' ? hook : entity[hook] ?? prototypeHook;
            return handler.bind(entity);
        }));
        for (const listener of this.listeners[event] || []) {
            const entities = this.entities.get(listener);
            if (entities.length === 0 || !entity || entities.includes(entity.constructor.name)) {
                listeners.push(listener[event].bind(listener));
            }
        }
        if (event === enums_1.EventType.onInit) {
            return listeners.forEach(listener => listener(args));
        }
        return utils_1.Utils.runSerial(listeners, listener => listener(args));
    }
    hasListeners(event, meta) {
        const cacheKey = meta._id + enums_1.EventTypeMap[event];
        if (this.cache.has(cacheKey)) {
            return this.cache.get(cacheKey);
        }
        const hasHooks = meta.hooks[event]?.length;
        if (hasHooks) {
            this.cache.set(cacheKey, true);
            return true;
        }
        for (const listener of this.listeners[event] ?? []) {
            const entities = this.entities.get(listener);
            if (entities.length === 0 || entities.includes(meta.className)) {
                this.cache.set(cacheKey, true);
                return true;
            }
        }
        this.cache.set(cacheKey, false);
        return false;
    }
    clone() {
        return new EventManager(this.subscribers);
    }
    getSubscribedEntities(listener) {
        if (!listener.getSubscribedEntities) {
            return [];
        }
        return listener.getSubscribedEntities().map(name => utils_1.Utils.className(name));
    }
}
exports.EventManager = EventManager;